Nikon MH-34 Battery Charger

Daniel is right. According to Nikon staff in the Nikon EH-8P Product Forum, the rated inputs and outputs of the EH-8P AC Adapter are as follows: Input: AC 100-240V 50/60Hz 1.5A Output: DC 5.0V/3.0A,15.0W; DC 9.0V/3.0A, 27.0W; DC 15.0V/3.0A, 45.0W; DC 20.0V/2.25A, 45.0W I have the MH-33, which is also a new charger that also has a USB-C PD port (like the MH-34 and your phone.) The MH-33 is for the bigger EN-EL18 battery. I'm guessing the Watt output depends on how much your charger or device is asking for. I have the EH-8P and the UC‑E25 USB cable, and they work fine for directly charging the Z9, Z8 and D780, as well as the EN-E:18c, and d in the MH-33. I also use my girlfriend's 45W Samsung Phone brick and they charge my Nikon USB-C stuff just as well. So does my iPhones 30W power brick and USB-C cable. So I usually just charge with whatever USB-C cable is closest. The worst I've experienced is the charge lamp just doesn't light up. But then I walk over to another plugged in charger and if I see the charge lights I know I'm good.

The Nikon MH-34 Battery Charger does have indicator lights to let you know how much of the battery is charged during the charging cycle.

It doesn't have a wall plug like the old charger, just a USB-C input labeled PD for Power Delivery. Best case scenario you have a powerstrip on your desk and can just plug in the USB-C cable as you would your phone. Otherwise, you have a brick in the wall and a cord dangling down to to the floor plugged into your Nikon gear. I purchased the Nikon-brand EH-8P AC adapter and UC-E25 USB-C cable to power the MH-33 (EN-EL18 batteries) as well as directly into the new Z cameras. I purchased two of each actually which came to around $200 and in hindsight this was an expensive lesson.. This is because Nikon doesn't publish power specs or requirements of their USB-C powered devices and chargers, and I didn't want to risk voiding any warranties.. That said, their MH-34 product page states "The MH-34 needs to connect to an EH-8P AC adapter...or third-party AC adapters that support USB PowerDelivery." So now I plug my cameras and charges into my 30W iPhone brick with a regular USB-C cable, or use my girlfriend's 45W Samsung brick with its USB-C cable, rather than fishing around in the drawer for the $100 Nikon brick and cord. Never had a problem (knock on wood), but personally I would err on sticking to reputable brands. I have at least 4 of the MH-25a chargers, which charge any EN-EL15 battery not just the B and C versions. I also have a ton of wall plugs and figure-8 cables so I never worry about charging. I never completely deplete a battery so if I'm getting ready for a shoot I'll just plug 4 EN-EL15c's in whatever state to the old chargers and at least two are done by the tie I'm ready to head out.